Telephone-circuit.



No. 691L245. Patented Jan. I4, I902.

W. K. 000K.

TELEPHONE cmcun.

(Application filed Aug. 5, 1901.)

(Nu Model.)

INVENTOR BY imam-K600i,

v A TTORNEY.

. UN TE 'ATENT- OFFICE.

WALTER K. COOK,OF M'AsoN'oHnioWn, ASSIGNOR or ONE-FOURTH To HARRY-E. sonsnn, on MASON crrY, IOWA.

TELEPHONE-CI CUIT.-

srncznxcsrron forming part or Letters Patent N0. 691,245, dated January '14, 1902.

Application filed August 5, 190}. Serial No. 70,969. (No model.)

To aZZ whom it may concern:

Be it known that I, WALTERK. CooK a citi zen of the United States, and'a resident of Mason City, county of Cerro Gordo, andState of Iowa, have invented certain new and usefu-l Improvements in Telephone-Circuits, of,

which the following isa specification, andwhich are illustrated in the accompanying drawings, forming apart thereof.

IO This invention relates to telephone-circuits.

In the practice of telephony the one-Wire or grounded circuit was originally-exclusively vused but in many instances and particularly in cities the disturbances due to neighboring I 5 wires from electric railway and lighting plants, as well as earth-currents, caused such serious noises in thojtelephone as to materially impair the efficiency of the service and render conversation e'xtremely'difiicult. The remedy for these dilficulties encountered in fthe grounded circuit was found in the metallic circuit--that is, by the substitution of aretnrn-Wire for the ground-and at the present day the metallic has incertain loca-' tions almost entirely superseded the ground circuit. When, however, the metallic circuit-alone is employed, asis always the case so far as I am aware, anyimpairment of the line-wires-suchas a cross, ground, or go break-puts the circuit out of service until the line-wires have been repaired, and this entails delays and'sometimes great incon venience, as will readily be perceived. The pres ent invention is designed to overcome this 3 5 evil, and has for its primary object to provide vmeans for converting an ordinary metallic circuit to a grounded circuit, suitable wiring being provided for the purpose, so that in the event of. any impairment of the line-wires, 4o irrespective of the character of the difficulty, whether it be a grounding, crossed wires, or a break in the line, the grounded circuit may be thrown into service, provided one of the line-wires of the metallic circuit remains in- 5 tact. The wiring for the two circuits traverses a board, one such board being located at each toll-station along the line and interposed between the line-wires and the telephone, and preferably,for convenience,within reach from the telephone and provided with suitable.

switches for cutting in and out the circuits.

' Referringto theaccoznpanying drawings, Figure 1 is a plan of the board, showing the invention applied to a leg-station. Fig. 2 is a diagrammatic view of the wiring of the board shown in Fig. '1; and Fig. 3 is a plan o f the board and switch mechanism adapted to a loop-station, the wiring on the under side of the board being shown in dotted lines.

The wiring ofthe circuits is run under a board A, which board also carries the necessary switches, bindingposts, switch-legs, and resistances, to be hereinafter referred to. Thewiring of the metallic circuit will be ex. plained first. The telephone-wires are connected to the binding-posts 10 11, the circuit being led from the former post by a wire 12 to the switch-leg 13, thence across by the bar 14 of a switch 15 to the post 16. From the post 16 a wire 17 passes to thebiuding-post 18, to which one of the line-wires is connected. The-return is from the binding-post 19 of the other linewire through the wire 20 to the post 21, thence acrossthe bar 22 parallel with the bar-:14 of 7 5 the switch 15 to the switch-leg 23 and along the wire 24 to the telephone-wire binding-post 11. This is the ordinary'course of the 'current when the metallic .circuit is in service.

It now a break in the line occurs ora crossing of wires or a grounding, the metallic circuit is put out of use and no message can be transmitted over that line until the damage has been repaired. For cutting in the groundcircuit'the switch 15 is thrown to theright; This switch consists of the pair of parallel bars 14 and 22, heretofore referred to, and

which are pivoted to the posts ,16 and 21 and insulated from each other by a block 25, from which the handle 26 projects. The switch 15 no also carries another metallic bar 27, which v may be supported as shown-that is, by Securing the same to the bar 14 through insulating-blocks 28. Z n

Located at the opposite side of the posts 16 5' and 21 to the switch-legs 13 and 23 are corresponding switch-legs 29 30 to receive the bars 22 and 14 when the switch -15 is thrown to the position illustrated in Fig. 1. In this p'osi: tion the bar 27 connects the switch-legs 31, mo and 32, and the object of this arrangement will appear hereinafter. I

stroycd.

Let it be assumed that the metallic system is in service, the switch heingjn the position shown in dotted lines, Fig. 1.. If a ground-v ing, crossingof wires, or a break should ccur -say in the line-wire connecting with the post 19the metallic circuit is of course de- The switch is then thrown to the right, cutting out the metallic circuit, and the following results: Starting from the telephone-wire binding-post 10, the connection being broken through the switch-leg 13 and the post 16, the current travels along the wire into the resistance 34 and is led therefrom by the wire 35 to the post 36 across a cut-out lever 37, pivoted to the said post and engaging the leg 38, thence by a wire 39 to the switch-leg 30, through the bar 14 of the switch 15 to the post 16,ancl by the wire 17 to the line-wire biddin g-post 18. The return is through the ground to the binding-post 40, which is connected by a wire 41 to the switch-leg 32, thenceacross the bar 27 to the leg 31, a'wire 42 leading from- ,the latter to the post 23, and finally by the wire 24 to the telephone-wire binding-post 11.-

If the line-wire connecting with the post 18 be the defective one, then the circuit travels from the telephone to "the binding-post 10, into'the resistance43 by the wire 33, and out through the wire 44 to the. post 45, across the cut-out lever 46, similar to 37 and located at the opposite side of the resistances 34 43120 the leg 47. From the latter'a wire 48 leads to the switch-leg 29, and the current crosses the bar 22 of the switch 15 to the post 21 and. then through the wire 20 to the line-wire bind-- ing-post 19. The return is from the ground to the post and then to the telephone, as heretofore described. The resistances 34 43- are preferahlybridged, as shown in Fig. 2, in

order that one wire, as 33, may serve for lead v For convenience in explanation I havedeslgnated the line-wires running into the board East and West. The wires running to the telephone are connected to the binding-posts 49 and 50. The outgoing current travels from the post 49 through a wire 51 to the switch-leg 52, thence across the bar 53 of a switch 54, similar to the switch 15, (shown in Fig. 1,) to the post 55. From the post 55 a wire 56 runs to a post 57, leading the circuit across the bar 5801: the cut-out 65 to the leg 59, and from the latter a wire 60 passes to the post 61, to which the outgoing east wire is connected. The return is to the binding-post 62, thence by the wire 63 to the switch-leg 64, across the bar 65 of the cut-out 65 to the post 66, through the wire 67 to the post 68, thence across the bar 69 of the switch .54 to the post 70, from which a wire 71 conducts to the telephone-wire binding-post 50. Referringto th'e'line-wires running west, the circuit is from the binding-post 49 through the wire 51 to the switch-leg 52, thence across the bar 53 of the switch 54 to the post 55. From the latter a wire 72 runsto the post 73 and the current passes through the bar 74 of the cutout 75 to the leg 76, and then through the wire 77 to the'line-wire binding-post. 78. The re-. tu'rni's from the binding-post 79 by the wire 80 to the switch-leg 81, across the bar '82 of the cut-out 75 to the post 83, thence by the wire 67 to the post 68, through the bar 69 of "the switch 54 to the switch-leg 7 0, and. tothe telephone-wire binding-post 50.by.the wire 71.

, The cut-outs 65 and 75 are similarin-cew struction, and the bars of each pair are insulated by blocks 84,as.sh'own. The object of these devices is to cut out thefline-wiresof one circuit when'the other is being used, as will be readily understood, although both are closed when the telephone atthe station is not is service, the line-wires then simply running-through the station;

To cut out the metallic circuit-and convert the same into agronnded circuit, the'switch 54 is thrown to the right, as'in the'case of the leg-station, previously described. Tracing out the circuit, assuming for the purpose that the'eastline-wireeonnecting with the binding post 62 is defective 'byreason "of n" break or other fault from the binding-post- 49, a wire leads; into the resistance of a pair-86 87'sin1ilar tothe resistances 34 43 of Figs. 1 and 2 and out by the wire 88 to the post 89, across the cut-out lever 90 into the switch-leg 91,51nd themthrough the wire 92,- the switch-bar'53, and wire 56 to the post 57',- rwhen'ce thecurrent passes across. the bar 58.

of the cut-out 65 to the line-wire binding- 62 being bad, the return is t-hroughthe ground to a post 93, through the wire 94 to the switchleg 95, thence across the bar .96, carried by and insulated from the bar 53 of the switch 54, to thes'witch'leg 97. From the latter a -.wire 98f-1eads to the post 70, which is connected f to the telephone-wire binding-post 50 by the wire 71, thereby completing. the ground-circuit.

Of course line running we'st when the line east is on a ground-circuit, the former line being intact,

the switch 54 may be thrown back to the left" and the metallic circuit .to the west be recs-- tablished.

post 61. The wire connecting with the post I 12o it it is desired to talk over the It is thought to be unnecessary todescribe the circuit through the other lines, as the same will be readily understood by reference to the wiring of the board;

It will be seen that by the invention in a loop-station if one lineas, for instance, the

east, referring to the drawings-is put outof service on a metallic circuit, it maybe other line, or West, may be used metallic simply by-shifting the switch as occasion requires.

I claim as my invention- 1. In a telephone-circuit, in combination, a

-metallic circuit normally in service, a pair of telephonete'rminals therein, a grounded line normally out of ser. "Ice, and means for disconnecting one of the telephone-terminals.

from the metallic circuit and connecting it with the grounded line. i

2. In a telephone-circuit, in combination, a metallic return-circuit, a pair of telephoneterminals, a grounded line, means for connecting each of the telephone-terminals with one limb of the metallic circuit, and means for connecting one of such terminals with both limbs of the metalliccircuit' and'theother with the grounded line.

3. In a telephone-circuit, in combination, a metallic circuit, telephone-terminals therein, a grounded line, a switch incorporated in the metallic circuit-and for cutting in when thrown, one terminal with the grounded line and the other terminal with one of the branches of the metallic circuit.

4. In a telephone-circuit, in combination, a-

metallic circuit, telephone-terminals therein,

a grounded line, branches leading from one of the terminals, and a switch incorporated in the metallic circuit and for cnttingin when thrown, one terminal with the grounded line and the-branches from the other terminal with the branches of the metallic circuit.

5. In a telephone-circuit, in combination, a metallic circuit, telephone-terminals therein,

a grounded line, a wire leading from one ter minal, a resistance in the path of said wire, and a switch incorporated in the metallic circuit and for cutting in when thrown one terminal with the grounded line and the wire leading from the other terminal with one of the branches of the metallic circuit.

6. Ina telephone-circuit, in combination, a metallic circuit, telephone'terminals therein,

agrounded line, a wire leading from oneterwith one or both path of the last-mentionedline, a branch wire running from each resistance, and a switch I incorporated in the metallic circuit and for cutting in when thrown one terminal with the grounded line and each branch wire with one of the branches of the metallic circuit.

7; In a telephone-circuit, incombination, a metallic circuit, telephone-terminals therein, a wire leading from one of the terminals, a pair of resistances in bridge with the said wire, a branch leading from each resistance 6c to a line-wire terminal, a cut-out in each of' said branches, and a-switch incorporated in the metallic circuit andrfor cutting out the metallic circuit andestablishing a ground circuit through 1 the ground-wire and the branches connecting with the line-wire ter-. minals.

8. In atelep'hone-circuit, in combination, a metallic circuit, a pairof telephone-terminals,

a grounded line, and means for connecting one of the telephone-terminals alternately with one of the metallic-circuit branches and the grounded line, and the other alternately of the metallic circuit I branches. ,75

9. In a telephone-circuit, in combination, a metallic circuit" normally in service, telephone-terminals therein, a grounded line normally out of service, means for connecting one of the telephone terminals with the 8 0 grounded line and for introducing a resistance between the other terminal and one of thebranches of the metallic circuit.

10. In a telephone-circuit, iii-combination,

ametallic circuit, telephone-terminals there- 85.

in, a grounded line, branches leading from one of the terminals, a cut-out in each of said:

branches, and a switch incorporated-in the metallic circuit for cutting in when thrown one terminal with the grounded line and each 'of the branches fromthe other terminal with one of the branches of the metallic circuit.

7 Y-WALTER K. 000K;- Witn'esses:

1E. E. WISE, A ANTHONY B. SEIBOLD. 

